Google showed off the LG G Watch, Samsung Gear Live, and Moto 360 smartwatches running its Android Wear software at Google I/O today. We first saw Android Wear when Google announced it in March this year, and now the first devices will be available today. LG and Samsung's devices will be available for order on the Google Play Store later today, while Motorola's watch will launch later this year. No pricing has been revealed yet.

As we've previously seen, LG's G Watch has a square face, while the Motorola Moto 360 is round. David Singleton, director of engineering for Google, said Android Wear devices will be available with both rectangular and circular screens and will come in a "wide variety of fashionable designs."

In the demo, we saw voice commands, OK Google searches, notifications, and other actions being performed on the devices. All Android Wear devices will have an always on display, and useful features like a voice dialer, music player and device controller. They'll also be at least somewhat water resistant. Some may also include heart-rate monitors and pedometers.

"We're right at the beginning of a new phase of the miniaturization of technology, which means it's finally possible to make a small computer that can fit comfortably on your body all day long," Singleton said. "The watch will act as your key in a multiscreen world," Singleton said.